tft filter

Hello, I am attempting to use a nec 1510+ tft on an ohp. Its a bit of a nightmare because I have to extend a bloody ffc cable. Whats puzzling though is when I test it on my ohp (with half the inverter and crap on top blocking half the screen) it does not output anything. I can see the tft working but the light is not getting though. There is a mirrored type plastic filter taped to the back of the glass. When I stripped the tft I removed all the other filters but this one is fixed on with rubbery type tape. If I remove this I will not be able to put it back on easily. I want to know if I can remove this to sort the darkness of the output. I have a 400w ohp so that is not the problem. This is such a newbie question that I cant find it in the other forums. Also I need to extend an 10 ffc cable. I bought a the 20ffc from lumen and cut it in half and am thinking of separating each conection and soldering them indivdually. Is there a better way than this (I have tried superglue but it only partially worked). Thanks for any help.
It is likely a fresnel lens, but not one that you would like to have in there! Is it a funny mirror finish on a very thin, flexible plastic sheet? If you run your fingers on it in one direction is it smooth and the other has sounds like ... well, like itself, but increasing pitch with speed of fingers? If not, peel back one corner and test the other side. It will be a strange sort of translucent if it is what I am thinking of, with different effects depending on how close it is to something.

If so, peel it off; it is there to ensure that the light from the backlight goes straight from whatever angle it came in from as originally applied. The LCD itself should look like nothing so much as dark glass when power is off.

If I am right you should see what you thought you would see, after peeling the lens off.